Method of utilizing the latent heat of steam in steam-power apparatus.



No. 676,685. Patented June I8, IQOI.

0. P. STERGREN. v METHOD 0F UTILIZING THE LATENT HEAT 0F STEAM IH STEAMPDWER APPARATUS.

(Application led June 19,1900.)

UNITEDA STATES PATENT QEETCE.

OSCAR P. CSTERCREN, oE NEW YORK, N. Y., AsSIeNoRTO THE osTERCRENMANUFACTURING COMPANY, OE NEw JERSEY.

METHOD 0F UTILIZING THE LATENT HEAT 0F STEAM IN STEAM-POWER APPARATUS.'

SPEGIFCA'IION forming part of Letters Patent No. 676,685, dated June 18,1901. Application fued im 19,1900. serrano. 20,307. (Nomad.)

To all whom it may concern:

Be it known that I, OSCAR P. OSTERCREN, a subject of theKing of Swedenand Norway, and a resident of Bedford Park, borough of the Bronx, cityand State of New York, have invented certain new and useful Improvementsin Methods of Utilizing the Latent Heat of the Steam in Steam-PowerApparatus, of which the following is a specification.

My invention consists of an improved method of utilizing the latent heatof the steam for useful effect in steam-power apparatus.

Various contrivances of apparatus may be employed for carrying out theinvention.

The form of apparatus that I have chosen for illustration in the presentcase is represented in the accompanying drawings, in which- Figure l ismainly a sectional elevation of the apparatus; but some of the parts arerepresented in side view. LFigl 2 is a detail in section in the line 22, Fig. l. Fig. 3 is a detail consisting of a vertical section th'roughthe boiler to show the pipe connections more clearly. Fig. 4: is adetail consisting of a vertical section of the upper portion of thepreheater and condenser to show th'e connection of the exhaust-pipe ofthe motor-engine.

The basis of the apparatus is a steam-generator, motor engine andcompressed air heater, air compressor, steam condenser, mixer of the airand steam, and preferably a superheater.

The steam-generator, air-mixer, and superheater may of course beconstructed in various ways; but the most desirable form at presentdeveloped consists of the A-shaped boiler, comprising the base-drums d,steam-drum b, two sets of inclined water-tubes c, respectively connectedat their lower ends in the drums a. and at their upper ends connectedinto the steam-drum b, two other sets of inclined water-tubes e, alsoconnected at their lower ends into the drums ct and at their upper endsconnected into the steam-drum b, also the two series of horizontalsuperheating-tubes d, intermediate of the tubes c e of each side,respectively, and also the cm'l of air-heating tubes fin the steam-drum.The tubes c of the inner rows are placed close together to form abaffling-wall against the hot gases from the iire-grate\2 upward nearlyto the steam-drum, where the alternate tubes of said row are defiectedinward, as represented at 3, for passages through said wall, and theinnerV rows of said tubes c are more openly disposed for downwardpassage and for direct impingement of the gases on tubes d, and theouter tubes e are also separated for upward passages. Alternate tubes ofthe inner rows of Series c are also deflected inward at the bottom a tofacilitate connection with the drums. Feed water is injected into thedrums a at g and circulates upwardly through the tubes c into thesteam-drum and downwardly through tubes c. The steam-pipe ZL takes steamaway from the boiler directly, and pipe 7l takes combined steam and airfrom the superheating-tubes d, the compressed air being supplied theretofrom the pipe j through the coil f. in steam-drum b, and thence intotubes d, and steam enters coil f from the steam-dome la at Z.

The motor-engine is in this case a tandem compound comprising ahigh-pressure jacketed cylinder m and the low-pressure cylinder n, alsojacketed, with an air-compressing cylinder o and piston directlyconnected on the same piston-rod.

A reheater for the exhaust-vapor from the high-pressure cylinder m isprovided atg for heating said exhaust by live steam from the boilerbefore entering the low-pressure cylinder, which consists of the hollowcylinder s, receiving the exhaust from cylinder m through pipe t andcontaining the live-steamreceiving head u at one end and a multitude oftubes o, discharging from said head into the collecting-chamber w at theother end, from which the steam enters the jacket or, of cylinder nthrough pipe r.

The jacketg/ of cylinder misin connection with the steam-pipe h by thebranch e for heating it by steam directly from the steamdrum. The waterof condensation in the jackets is returned as feed-water to the boilerby one of the injectors g.

For combining compressed air with steam as a means of utilizing thelatent heat of the steam for useful work, as before stated, anair-compressor is employed and with it a heater for the compressed airfor preheating the air by the exhaust-vapor of the motor-engineintermediately ofthe compressor and the boiler. Any form of compressormay be used; but the one herein represented comprises thecompressing-cylinder 0,before mentioned and a pair of coolers formingpart of the compressing apparatus, as follows, said coolers consistingof the hollow cylinders 5, set upright on the funnel-mouths 6 of thecylinderports, respectively, and each containing a multitude of tubes 7,communicating with a collectingchamber 8 in the upper end 0i' saideylinder,into which the air is received through suction-pipe 0 and valve10. Water packing is employed in the cylinder and coolers in suchquantity in each that the air will be forced out through theeduction-valves 1l alternately on its way tothe preheater as the pistonarrives at the ends of its strolresnespectively. Cooling water admittedthrough a supply-pipe 12 and discharged through pipe 15 circulatesthrough the cylinders 5 around the tubes 7 for cooling the air tofacilitate compression. A pipe 13 connects with the supply-pipe forcooling-water and with the 'funnels 6 of the coolers to replenish thesupply of packing-water from time to time as it may be reduced byabsorption vby the' air. Said pipe is controlled by a cock 14. This formof compressor is particularly favorable for use as an element of myimproved engine because of the isothermal distribution by the waterpacking of the heat generated by the compression, whereby higherefficiency is obtained both in compressing and cooling.

A feed-pump 16 is connected with the suction-pipe 9 of the compressor.When starting the engine, the pump receives the air through asuction-valve 17 and discharging it into the suction-pipe 9 of thecompressor through eduction-valve 18 and pipe 19. It is desirable thatthe pressure of air in the compressor be maintained at a certain limit,for which a relief-valve 2O is attached to the pipe 19, which iscontrolled by a spring 21, provided with an adjusting-screw 22, whichmay be set for escape of pressure above any predetermined point. Most ofthe air to be compressed will, however, be recovered from the preheater,into which the exhaust of combined air and steam from the low-pressu recylinder is discharged through pipe 23, this air being drawn by thesuction of the compressor-pump '0 through pipe 35 into suction-pipe 9,said pipe 35 being suitably connected with the preheater.

The preheater consists of the upright hollow cylinder 24, having anenlargement of the lower end for a hot-well 25 and containing in theupper part of said hot-well a receiving-chamber 26 for reception of thecompressed air through discharge-pipe 27 of the compressor. Thereceiving chamber 26 is connected with a collecting-chamber 2S in theupper part of cylinder 24 by a multitude of tubes 29, through which thecompressed air passes and which are surrounded by the ex# haust fromcylinder n, which enters at 30 near the upper end of cylinder 24,passing downward along the tubes in the opposite direction of theascending air in the tubes. The cold air from the cooler condenses thesteam, which gives up most of its heat, especially the latent heat, tothe air and falls into the hot-well 25 as water, from which it isreturned to the boiler as feed-water by one of the injectors g. Someheat is also contributed by the hot air combined with and exhaustingwith the steam. The air thus compressed and then heated, being in agaseous state, expands in due proportion for every increment of heatabsorbed, and thus converts the latent heat of the steam into powerwithout any loss, while water either preheated or heated in the boilermust first be supplied with its enormous proportion of latent heatbefore being endowed with effective power, the latent heat going towaste without contributing effective force. The air thus heated entersthe superheating-coil j' through pipe j, in which is a cheek valve 31,preventing backiiow, and steam enters along with the air issuing fromcoil f at 40, and they enter the superheaters 4c together throughbranches 11 and mix therein.

When starting the engine, live steam from the pipe h is first admittedto cylinder m through-valve 32 in a connecting-passage betweensteam-pipe 71, and the combined steam and air pipe t', valve 33 in thelatter pipe being closed. This serves to operate the engine until asufficient amount of air is accumulated in the system by means ot thefeed-V pump 16 and com presser for the proper working of the engine,backiiow from the boiler being in the meantime prevented by thecheck-valve 31. When air-pressure has accumulated suciently in thecompressor and preheater to pass check-valve 31 into the generator,valve 32 is to be closed and valve 33 opened for the regular operationof the en= gine. Valve 34, admitting live steam into the preheater q andthe steam-jackets of the cylinders, may be opened to begin with. The airafter being compressed isothermally will rst absorb all available heatfrom the ex; haust-vapors and will then in passing through the tubes-fin the steam-drum rise to the temperature of the surrounding steam, andtherefrom will branch out, along with the steam entering from thesteam-drum through pipe 1, into the two systems of superheating-tubes e,where the steam and air will be more thoroughly mixed and superheatedfor greater efciency before entering the motor-engine.

Whatever waste of heat there is in this engine is what is carried awayin the coolingwaterof the compressor in preparing the compressed air totake up the heat of the exhaust-vapors, no part of which is wasted,provided the preheater be properly insulated, and which,including thelatent heat,is largely in excess of that expended in the cooling- IOOWater and manifestly greater than the power expended in compressing theair.

Good results may be had Without the superheater in the steam-generator,and the invention is not therefore limited to the use of it; but greaterefficiency is obtained by the use of it. Nor isthe invention limited tothe use of a reheater intermediate of the high and low pressurecylinders of the motor-engine.

l/Vhat I claim as my invention isl. The method of utilizing the latentheat of the exhaust-steam of a steam-engine for useful effect in saidengine, which consists in using air or other gaseous body together withsteam as the motor fluid, condensing the spent steam and transferringthe heat given up in the condensation of said' spent steam to suchgaseous body, and injecting said body into the boiler as a vehicle forreturning said heat thereto for further useful eect in said engine.

2. The method of utilizing the latent heat of the exhaust-steam of asteam-engine for useful effect in said engine, which consists in usingair or other gaseous body, together With the steam as the motor fluid,condensing the spent steam, recooling and compressing the gaseous bodyseparated from the condensed steam, and using it for effecting thecondensation and for recovering the heat thereof, and returning saidreheated gaseous body to the boiler for use together with the steam inthe engine.

Signed at New York city this 13th day of J une, 1900. A

OSCAR P. OSTERGREN. Witnesses:

C. SEDGWICK,

J. M. HOWARD;

